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Updated: Jul 16, 2026

Assessment of Sarcoplasmic Reticulum Calcium Reserve and Intracellular Diastolic Calcium Removal in Isolated Ventricular Cardiomyocytes
Published on: September 18, 2017
Alteration of myocardial sarcoplasmic reticulum Ca2+-ATPase and Na+-Ca2+ exchanger expression in human left
Przemyslaw Leszek1, Malgorzata Szperl, Anna Klisiewicz
1Heart Failure and Transplantology Department, National Institute of Cardiology, 04-628 Warsaw, Alpejska 42 St, Poland. leszekp@ikard.pl <leszekp@ikard.pl>
Background:
Reduced myocardial contractility is often attributed to altered Ca(2+) transients and expression of Ca(2+)-ATPase of the SR (SERCA) and Na+/Ca(2+)exchanger (NCX) genes.
Aims:
To assess myocardial expression of SERCA and NCX protein levels in left ventricular (LV) remodelling due to chronic severe mitral regurgitation (MR).
Methods:
Myocardial expression of SERCA/NCX in biopsy specimens obtained during mitral surgery was assessed in 36 MR patients with LV remodelling and plasma neurohumoral/cytokine activation and in four non-failing hearts (NFH).
Results:
Myocardial protein levels of SERCA were significantly (20%) lower in the MR group than in NFH group (p=0.016). No significant changes in NCX were observed. However, a lack of homogeneity with regard to SERCA/NCX proteins was observed. Moreover, SERCA was negatively correlated with BNP (r=-0.49, p=0.02), TNFalpha (r=-0.68, p=0.0005) and IL-6 (r=-0.52, p=0.02), whereas NCX was only negatively correlated with TNFalpha (r=-0.62, p=0.002).
Conclusions:
MR patients showed wide variations in SERCA/NCX protein expression. Myocardial protein levels of SERCA were significantly lower in the MR population. Moreover, a correlation between BNP, cytokines (IL-6, TNFalpha) and the expression of SERCA/NCX proteins was observed.
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